Safety retaining mechanism for mine cages, lifts, and the like



Jan. 30, 1923. 1,443,882

H. LYDEARD. SAFETY RETAINING MECHAN'SM FOR MINE CAGES, LIFTS, AND THELIKE; FILED JuNE19. 1922.

of the cage upon failure of the Patented Jan. 30, 1923.

tli'iE ST-TS HERBERT LYDEARD, or SWINDON, ENGLAND.

SAFETY RETAINING MEorrANIsi/i: EORMINE cases, mars, AND THE LIKE.

Application filed. June 19,

Tov all whom it may concern Be it known that I, HERBERT LYDEARD,"subject of the King of Great Britain, resid ing at 96 Beatrice Street,Swindon, W'iltshire, England, have invented new and useful Improvementsin Safety Retaining Mechanism for Mine Cages, Lifts, and the like; and Ido hereby declare the following to be a full, clear, and exactdescription in the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

This invention relates to a safety device for mine cages, lifts and thelike which will serve to arrest the downward motion of the cage or thelike should the lifting cable or its equivalent break, and has for itsobject to provide a simple .device which will be more eflicient inaction than existing devices of this type.

According to my invention a guide member is provided having normallyfreely disposed therein a ball or balls adapted to be brought intoengagement with a guide rope or stay or the equivalent thereof in suchmanner as to arrest. downward movement supporting means.

In carrying my invention into practical have appended hereto one sheetof. drawings illustrating same wherein Fig. 1 is a view showing myinventionapplied to a mine cage of known construction.

F 2 is a diagonal sectional view 'of a cage illustrating the embodimentof my invention.

Fig. 3 is a sectional view of a gripping device in the inoperative orfree position.

Fig. i is a sectional view of a gripping device in its operative orgripping position.

Referring .to the drawings the cage 1 which may be of any known type issupported for lifting or lowering by means of a cable 2 connected to anysuitable operating mechanism not shown, whilst the usual guide ropes orstays 3 are provided passing through suitable guides at each corner ofthe cage.

The cable 2 supports the cage by being connected either directly orindirectly to a weighted member 5 slidably supported within a sleeve 6firmly secured to the roof or other suitable part of the cage. For thispurpose the upper end of the weighted member is provided with a loop 7or other suitable means for the attachment of the cable 1922. SerialNo.569,403.

9 or a connecting piece 2. The upper end of this weighted member isalsov flanged at 3 to prevent it falling through thesleeve t3. Securedto thelower end of 'theweighted member is an enlarged base portion 5.which serves to support the cage and further gives additional weight tothe member 5.

' This base 9 is provided with a circumferential groove 10 adapted toreceive the ends of a number of fulcrumed levers 11 fulcrumed tobrackets 12 depending from the roof or other suitable part of the cage.These fulcrumed levers are provided with horizontal arcuate ends 13 forthis purpose so that they fit freely in and conform to the curvature ofthe, circumferential groove 10. The outer ends-of the'levers 11 are eachformed with a blfurcated portion 14 which engages in a circumferentialgroove 15 provided around a'plunger 16. Each of these plunge-rs 16 iscylindrical and bored through its axial centre to receive a guide rope'or stay 3 and has a sliding fit through a collar 1'? screwed on to thebase of a guide 1,

so that the plunger is mainly disposed with- H in the guide 4.

The upper end of each of these plungers 16 is flanged at 18 so as toprevent it falling through the collar 17. This flanged portion istapered downwardly from the centre on its upper surface upon whichfreely rests a number of balls'l9 which owing to the taper of the uppersurface of the plunger tend to roll away from the guide rope or stay 3,and normally'i. e. when thecageis in working order, do not engage thesaid guide rope or stay but bear against the inner 1 wall of the guide4.

The guides 1 are of truncated cone formation having'their wallsconverging upwardly so that should the plungers 16 move upwardlyrelatively to the said guides the balls 19 will be gripped tightlybetween the guide ropes or stays 3 and the inner walls of the guides 4:,thereby preventing movement of the guides and consequently the cagealong the guide ropes or stays 3.

The operation of the device is as follows :Normally the lifting cable 2exerts a pull upon the weighted member 5 so that the inner ends of thefulcrumed levers 11 are maintained in their uppermost position whilstthe outer ends are maintained in their lowermost position so as to exerta pull downwardly upon the plungers 16 in which position the balls 19rest freely against the which would leave the cage unsupported by suchcable, the weightedmember 5 would immediately owing. to its own weightmove downwardly Within the sleeve 6 and so more the outer ends of thefulcrumed levers 1.1 upwardly which will cause the plungers 16 also tomove upwardly within the guides 41:

and so grip the balls tightly between the guide ropes or stays and theinner walls of the guides 4 whereby further downward motion of the cagewill be immediately arrested.

it will be clear from the foregoing that the greater the weight of thecage and its contents the more positive ill be the gripping action. ofthe balls upon the guide ropes should the cable break, so that it willbe no disadvantage from the point of view of the eiliciency of thesafety device to have excessive weights in the cage.

It will .be apparent that in some cases a pair of gripping. deviceswould serve the purpose instead of four. I

Hitherto it has been proposed to provide a safety device comprising aguide member having a tapered inner surface in whichis relativelymovable a sleeve carrying a number of balls in its wall, this sleevebeing adapted to be moved within the guide member by a weighted lever orspring, one end of the weighted lever being connected to the liftingcable.

What I claim is 1. The combination with guide stays, of a lift normallysuspended by. suitable tackle and mounted for movement along said stays,of means to arrest downward movement of the lift upon failure of itssuspension means comprising a plurality of gripping devicesone of whichis associated with each guide stay, a plurality of levers each of whichis movable to predetermined raised and lowered positions and one ofwhich is associated with each gripping device, said levers beingoperable when in raised position to hold said gripping devices releasedwith respect to said stays and being operable when in lowered positionto cause said gripping devices to grip said stays, a guide sleevesecured to the lift, a weight guided by and movable through said sleeveto preiaeasea determined raised and lowered positions, said weighthaving an annular groove, one end of each of said levers being disposedin said groove whereby all of the levers are movable simultaneously andcorrespondingly with the weight, said weight being maintained normallyraised by said suspension tackle thereby to maintain the levers raisedand the gripping devices released, so that upon failure of thesuspension tackle said weight moves to lowered stay passingtherethrough, and a plunger reciprocable within said guide member, saidplunger having its upper end tapered downwardly and outwardly,and.havinga plurality of balls resting thereon, whereby upon upwardmovement of said plunger said balls are forced inwardly into grippingengagement with the guide stay by the upwardly tapered wall of saidguide member and whereby upon downward movement of said plunger saidballs roll down the tapered upper end thereof and outwardly away fromsaid guide stay; and a connection between the suspension tackle and eachof said gripping devices whereby said plungers normally are held in adownward position to maintain the balls out of gripping relation withthe guide stays and whereby upon failure of the suspension tackle saidplungers are caused to more upwardly thereby to cause the balls togripsaid stays.

In witness whereof I have signed this specification in the presence oftwo witnesses. I

' HERBERT LYDEARD. in the presence of G. HUGHES,

C. L. HUGHES.

